Created
June 20, 2021 14:44
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#!/usr/bin/env python3 | |
""" | |
# NOTE, you must change the string below for data you want. | |
# This script does not take arguments in its current form. Sorry! | |
""" | |
from pwn import * | |
string = b"foobar" | |
full = "eax" | |
half = "ax" | |
little = "al" | |
pieces = [] | |
for i in range(0, len(string), 4): | |
chunk = string[i : i + 4] | |
pieces.append((hex(unpack(chunk, "all")), chunk.decode("utf-8"))) | |
counter = 0 | |
for each in pieces[::-1]: | |
piece, value = each | |
if len(piece) <= 10: | |
register = full | |
if len(piece) <= 6: | |
print(f'"xor {full}, {full};" # zero out {full}') | |
register = half | |
print(f'"mov {register}, {piece}"; # ensure nullbyte') | |
print(f"\"push {full};\" # end of string '{value}' with nullbyte") | |
counter += 1 | |
continue | |
if len(piece) <= 4: | |
print(f'"xor {full}, {full};" # zero out {full}') | |
register = little | |
print(f'"mov {register}, {piece};" # ensure nullbyte') | |
print(f"\"push {full};\" # end of string '{value}' with nullbyte") | |
counter += 1 | |
continue | |
if counter == 0: | |
print(f'"xor {full}, {full};" # zero out {full}') | |
print(f'"push {full};" # ensure nullbyte') | |
print(f"\"push {piece};\" # push '{value}' onto stack") | |
counter += 1 |
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hi John,
I've successfully used your script and added argument functionality. Here's the slight modified version: